Optical coherence tomography (OCT) is a technique for high-resolution depth profiling of a sample below the sample surface. In recent years, swept source optical coherence tomography (SSOCT) systems have demonstrated superior imaging speed, imaging range, and image quality. The key technology element of SSOCT systems is the wavelength swept laser source. The MEMS-tunable vertical cavity laser (MEMS-VCL) has proven to be an important key wavelength-swept source for SS-OCT at 1300 nm and 1050 nm, as described, for example in (I. Grulkowski, J Liu, B. Potsaid, V. Jayaraman, C. D. Lu, J. Jiang, A. E. Cable, J. S. Duker, and J. G. Fujimoto, “Retinal, anterior segment, and full-eye imaging using ultra-high speed swept source OCT with vertical cavity surface-emitting lasers,” Biomedical Optics Express, vol. 3, no. 11, pp. 2733-2751). For SS-OCT systems to be commercially viable, swept sources based on 1050 nm VCLs must provide substantially single longitudinal, transverse and polarization mode operation over a wide tuning range, be swept at hundreds of kHz rates for hundreds of billions of cycles, provide sufficient output power for SSOCT imaging, and be manufacturable and long-term reliable.
From the foregoing, it is clear that what is required is a MEMS-VCL at 1050 nm that meets tuning range, speed, coherence length, and output power requirements of SS-OCT systems, and is both manufacturable and long-term reliable.